package test;

public class dome1 {
    public static void main(String[] args) {
        int[] arr = new int[20];
        arr[0] = 1;
        arr[1] =1;
        for (int i = 2; i < arr.length; i++) {
            arr[i] =arr[i-1] +arr[i-2];

        }
        System.out.println("20月的对数为"+arr[19]);
    }
}
